In an existing drive method of an Active-Matrix Organic Light Emitting Diode (AMOLED), a data voltage is output by a drive circuit and written into a pixel circuit directly to control luminance of pixels. However, with the improvement of the performance of light emitting devices and resolutions of display panels, differences between data voltages corresponding to neighboring grey scales become smaller, so that the requirements of output accuracy of a drive circuit is increasingly higher. In this case, a drive circuit in the prior art has relatively low output accuracy, relatively high power consumption, and poor uniformity.